*Small correction: At 2:19 I incorrectly said “four fifths” and meant to say “four point five.”
0:00 Problem
1:00 Common mistake
3:14 Solution
My blog post for this video
https://wp.me/p6aMk-5h1
Sources
Toom, Andrei. “A Russian teacher in America.” Journal of Mathematical Behavior 12.2 (1993): 117-139. See the “Tom, Dick, and Harry working together problem” (page 134 in text). https://faculty.utrgv.edu/eleftherios.gkioulekas/OGS/Misc/ARUSSIAN.PDF
Jerome Dancis, Associate Professor Emeritus, University of Maryland, Algebraic word problems. www.math.umd.edu/~jnd/Algebraic_word_problems.pdf
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